A semiconductor device may have a highly integrated structure including a line layer having a spatial gap. Such devices, however, exhibit increased parasitic capacitance, thereby causing a delay in signal transfer and also signal interference.
In order to mitigate such problems, a semiconductor device may include a low-k dielectric as an insulating interlayer to fill the spatial gaps and an insulation layer between line patterns. A fluorine-doped oxide layer may be used as an insulating layer. The fluorine-doped oxide layer may have excellent characteristics for filling the narrow spatial gaps between lines and a low dielectric constant (low-k). The F-doped oxide layer may have a dielectric constant smaller than that of an undoped silicon oxide layer to suppress a signal transfer delay of a line. Moreover, the F-doped oxide layer having a good characteristic for filing a narrow gap is used as an inter-line insulating interlayer.
As illustrated in example FIG. 1, a semiconductor device may include first insulating layer 12 containing a hydroxyl radical formed on and/or over semiconductor substrate 10 and a line layer having a plurality of line patterns 14 on and/or over first insulating layer 12.
First insulating layer 12 may be used for interlayer insulation between line patterns 14 and lower line patterns or unit devices. Fluorine-doped (“F-doped”) oxide layer 16 may be formed on and/or over first insulating layer 12 to fill a spatial gap area between respective line patterns 14.
As an insulating interlayer or a capping layer beneath a line layer in a semiconductor device, a TEOS layer may be used. The TEOS layer has an intensive structure and a prescribed planarization characteristic and contains OH functional groups therein.
However, F-doped oxide layer 16 directly contacts insulating layer 12. Because fluorine has good diffusivity, F-doped oxide layer 16 reacts with the hydroxyl radical in first insulating layer 12 to form very corrosive HF. The HF induces a problem of forming bubbles within insulating layer 12 or causing corrosion in the metal or oxide.